Topmodel Ventus 2cx build and electric conversion

I have been looking at buying a Topmodel Ventus for nearly 2 years now and the opportunity to own one of these beauties finally presented itself to me. I picked up the plane at the ICARE warehouse whilst on holiday in Montreal.

As far as I am aware, there is no slope flying or aero-towing happening in my part of the woods, so I am going to mount an electric motor in the nose. Fortunately there are electric nose mounted sustainers on full scale gliders these days, so I can make a case for it being a scale glider (maybe the folding prop is a little on the big side) Also much more affordable than the commercial SLS units.http://soaringcafe.com/2011/03/maide...ulsion-system/

The Ventus came well packaged and had no damage. Everything was wrapped in bubble wrap or taped to the inside of the box. All-in-all it was a good first impression.

The fuselage comes with canopy already hinged and the latch is accessible through the canopy window. Retract, tail-wheel, tow-release and wire-harness were also installed. The gaps at the retract doors are a little bigger than what I would like, but still a very solid installation. Paying a little extra for the delux kit is totally worth it.

The wings are wood over foam, covered with oracover. Only on close inspection does one realise that it is not a moulded wing, yes it is that good. The wire-harness, wing retainer and spoilers were already installed. Flaps and ailerons were already hinged with tape. I hate it when they use the covering material as hinging material, so seeing tape hinges is a nice touch.

I started work on the wing by making 6 servo frames for the 125mg servos I am using on flaps and ailerons. I decided to use the supplied brass control-horns, but in retrospect I should have used fiberglass control-horns.

For spoilers I used 85mg servos wrapped in tape and glued them in place with gorilla glue.

After installing the wing servos, I started work on the wiring-harness. The wiring-harness and connectors at the wing root were already installed, but I still had to solder the servo leads onto the harness and attach servo plugs to the wires in the fuselage.

Next up was the most stressful part of the build, cutting the nose.
After measuring, marking and rechecking it a 100 times I committed to the cut. The last few millimeters I carefully did by sanding the nose by hand, till the spinner fitted perfectly.

I then wrapped the motor in tape and attached it to firewall. Next I coated the inside of the nose and firewall with 20min epoxy and slid the motor into place. Then attached the spinner to make sure everything is lined up properly, while waiting for the epoxy to set.

Looks good! About the only thing I could add is to dump the Z-bends at the servo arm and put another clevis there....over time the Z-bend will develope slop and you will start to get false neutrals and always have to retrim.

Looks good! About the only thing I could add is to dump the Z-bends at the servo arm and put another clevis there....over time the Z-bend will develope slop and you will start to get false neutrals and always have to retrim.

Why should this happen? Iíve got a couple of gliders, where the linkage has a Z-bend on one end (though theyíre not as big as the Ventus 2cx here in question) and didnít recognise a problem with false neutrals yet even after a couple of years flying them. Of course the diameter of the wire and the diameter of the hole in the servoarm or rudderhorn have to correspond to the 1/10th of a millimeter...

Thank you for the advice SZD16, but I have to agree with Bie. That said, I am planning to user metal clevises on both sides of the elevator control rod.

Z-bends are not as elegant as a metal clevis, but they are quick and easy to make. Z-bends are also a little forgiving if everything is not lined up properly. If I was using metal servo arms, I will then most definitely use metal clevises or ball links to get a slop free setup.

I always make sure that the hole for the wire in the plastic servo arm is a fraction smaller than the diameter of the wire I am using. That assures me a slop free setup. Over time the the hole in the plastic servo arm can get bigger and that has happened to me before with cheapo servos using soft plastics for their servo arms. I don't see how using a metal clevis will make the wear of a plastic servo arm significantly less.

I have the same ship and have also electrified mine with a nose prop. This suggestion is moot at this point since you have already glued in the mount - sorry, I only just saw the thread), but after using various glues over the years for mounting motors I've settled on West Systems G-Flex. It handles the vibration and is extremely tough. On the other hand, when using 20 minute epoxies years ago (such as Devcon) I have experienced them fracturing over time. I'd be concerned about using them for this application, especially in a ship at this price point.